Deriving the Schwarzschild solution

In summary, the conversation discusses the Schwarzschild solution, which is a metric that describes a static, spherically symmetric gravitational field surrounding a central mass. The solution involves solving R_{ab} = 0 and substituting the metric form into it. This can be done by calculating R_{tt} and R_{rr} using the Riemann curvature tensor and the equations for g_{tt} and g_{rr}. While this method may take a while, it is necessary and worth it.
  • #1
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Right so there's this part in my notes where we begin to derive the schwarzchild solution. There's a substitution part I don't understand fully (I think) but I'll start from the beginning...The Schwarzschild Solution.

The solution corresponds to the metric corresponding to a static, spherically symmetric gravitational field in the empty spacetime surrounding a central mass (like the Sun).

Choosing coordinates (t, r, θ, ϕ), it can be shown that a metric of this type is of the
form:

[tex]ds^2 = -e^{A(r)}dt^2 + e^{B(r)}dr^2 + r^2(d\theta^2 + sin^2(\theta)d\phi^2)[/tex] (6.8)

where A(r) and B(r) describe deviation of the metric from Minkowski spacetime. Note
that for constant t and r the metric reduces to the standard metric for the surface of a
sphere. As one is dealing with vacuum, one is poised to solve

[tex]R_{ab} = 0[/tex] (6.9)

Where (I'm pretty sure) [tex]R_{ab}[/tex] is the Ricci tensor.

Substituting (6.8) in (6.9) we have, after some algebra...

--------

Then there's expressions for [tex]R_{tt}[/tex], [tex]R_{rr}[/tex] etc...

But I don't know exactly how to sub 6.8 into 6.9!

Would I be right in thinking we just calculate... (When ab = tt)

[tex]R_{tt} = R^c_{tct} = 0[/tex] where [tex]R^c_{tct}[/tex] is the Riemann curvature tensor.

Then we can use that,

[tex]\Gamma^c_{ab} = \frac{1}{2}g^{cd}(\partial_a g_{bd} + \partial_b g_{ad} - \partial_d g_{ab})[/tex]

to calculate [tex]R^c_{tct}[/tex] where we have...

[tex]g_{tt} = -e^{A(r)}[/tex]
[tex]g_{rr} = e^{B(r)}[/tex]

and so on...

Is this the right method? Seems like it's going to take a loooong while to do this though.
 
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  • #2
Yes, this is the right method and Yes this will take a long while to do it. But it is worth it. Btw. you will only need [tex]R_{tt}, R_{rr}[/tex].
 

FAQ: Deriving the Schwarzschild solution

What is the Schwarzschild solution?

The Schwarzschild solution is a mathematical solution to Einstein's field equations in general relativity that describes the curvature of spacetime around a spherically symmetric, non-rotating mass. It was first derived by Karl Schwarzschild in 1916.

How is the Schwarzschild solution derived?

The Schwarzschild solution is derived by solving Einstein's field equations, which are a set of ten differential equations that describe the relationship between the curvature of spacetime and the distribution of matter and energy. The solution involves a coordinate transformation and the use of advanced mathematical techniques such as tensor calculus.

What is the significance of the Schwarzschild solution?

The Schwarzschild solution is significant because it was the first exact solution to Einstein's field equations and it provided a mathematical description of gravity that was consistent with Newton's theory of gravity. It also paved the way for further developments in understanding the nature of spacetime and black holes.

What are the assumptions made in deriving the Schwarzschild solution?

The Schwarzschild solution is derived under the assumption that the mass is spherically symmetric and non-rotating, and that the spacetime is empty (i.e. there is no matter or energy present). These assumptions allow for a simpler mathematical solution to Einstein's field equations.

What are some applications of the Schwarzschild solution?

The Schwarzschild solution has many applications in astrophysics and cosmology. It is used to study the properties of black holes, the bending of light by massive objects, and the evolution of the universe. It also plays a crucial role in the development of more complex solutions to Einstein's field equations.

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